VOOZH about

URL: https://oeis.org/A027361

⇱ A027361 - OEIS

login
A027361
Number of "sorted permutations": permutations that can occur as the output of the sorting procedure described by Knuth.
1
1, 1, 1, 2, 5, 17, 68, 326, 1780, 11033, 76028, 578290, 4803696, 43297358, 420639362, 4382320595, 48729809104, 576039659209, 7213070102518, 95373808983223, 1327842798808220, 19416307366048221, 297499363267839558, 4766432683120731044, 79699553284422816437, 1388383661114307067780, 25156549558328842669336
OFFSET
0,4
REFERENCES
D. E. Knuth, The Art of Computer Programming Vol. 1, p. 238.
LINKS
M. Bousquet-Mélou, Sorted or sortable permutations, Discrete Math., 225 (2000), 25-50.
J. West, Sorting twice through a stack, Theoret. Comput. Sci. 117 (1993) 303-313.
CROSSREFS
Cf. A027432.
Sequence in context: A051625 A056098 A239201 * A101971 A211387 A372376
KEYWORD
nonn,nice
EXTENSIONS
Prepended a(0)=1 to match offset, added more terms, Joerg Arndt, Jul 01 2014
STATUS
approved